1. Field of the Invention
The present invention relates to a method of and an apparatus for electronically processing an image, wherein stable color reproduction can be carried out in an image input/output apparatus, and to a correction chart suitable for use in the apparatus.
2. Description of the Related Art
An image scanning, reading, and reproducing system is widely used in the printing and platemaking fields, for example, for electronically processing image information stored in an original to be read so as to produce an original film plate with a view toward simplifying the entire process and improving the quality of printed images.
In an image reading apparatus which constructs the image scanning reading and reproducing system, an original positioned and stored in an original cassette is scanned to read image information.
In the image reading apparatus, in order to produce a film plate according to the purpose, a pre-scan operation is carried out to initially feed the original cassette to a reading unit and to set up processing conditions such as magnification, image processing, etc. Then, a main-scan operation is performed to set up the optimum processing conditions based on image information obtained by the pre-scan operation and to read image information again in accordance with the processing conditions referred to above.
When it is desired to subject the image information to the pre-scan operation and then to the mainscan operation in the above-described manner, the image processing conditions are automatically set up, thereby carrying out the image processing. However, there is no adequate method of processing color separation and correction. In addition, operation is inefficient because color adjustment is made for each original.